GB1579367A - Annular cooler for hot bulk material - Google Patents

Description

PATENT SPECIFICATION

( 11) 1 579 367 ( 21) Application No 13273/77 ( 22) Filed 29 March 1977 ( 31) Convention Application No.

2613462 ( 32) Filed 30 March 1979 in ( 33) Fed Rep of Germany (DE) ( 44) Complete Specification published 19 Nov 1980 ( 51) INT CL 3 F 27 D 15/02 ( 52) Index at acceptance F 4 B 7 B ( 72) Inventors DIERK MICHEL HARTMUT WOLERT HELMUT ERNST KLAUS MOLLER ( 54) ANNULAR COOLER FOR HOT BULK MATERIAL ( 71) We, METALLGESELLSCHAFT AKTIENGESELLSCHAFT, a body corporate organised under the Laws of the German Federal Republic, of 14 Reuterweg, Frankfurt am Main, German Federal Republic, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:-

This invention relates to a rotatable annular cooler for cooling hot bulk material, particularly hot sintered iron ore, and like material in the form of lumps.

Hot lumpy bulk material, particularly sintered iron ore, may be cooled in a rotatable annular cooler by cooling air flowing through the cooler The cooler has a cooling compartment, which is defined by inner and outer gas-permeable walls, the cooling air being blown in under pressure through the inner wall, flowing through the bulk material and escaping through the outer wall The cooling compartment may consist of individual cells arranged one beside the other in a circle or may comprise two concentric annular walls The hot bulk material is charged into the cooling compartment from above, and when it has been cooled is scraped by a scraper from a bottom plate of the cooler When the cooling air flows horizontally through the cooling compartment, the thickness of the layer formed by the material is limited by the pressure to be applied, whereas the height of the material is limited only by the permissible loads on wheels on which the cooler is carried For this reason these coolers require only a relatively small floor space Similar coolers have been disclosed which have one annular cooling compartment or two annular concentric cooling compartments and which are concentrically guided by a central bearing and require a carrying frame which spans the inner space Besides, the cooling compartments are firmly integrated in the carrying frame so that thermal stresses tending to cause deformation may arise in the carrying frame Moreover, the carrying frame is subjected to heavy wear due to mechanical 50 abrasion of those parts which are contacted by the material being cooled.

Annular coolers having a cooling compartment which is discharged through the bottom are also either concentrically guided 55 by a central bearing or require for this purpose two track rails having flanges which are subjected to heavy wear so that high loads are applied, particularly in the wheel bearings 60 In connection with annular coolers in which the cooling air is blown through a gas-permeable bottom so that they can be operated only when the depth of material being cooled is small, it has been proposed 65 concentrically to guide the cooler by means of track rollers, which are guided on a horizontal circular rail These coolers are discharged at the bottom or at the side and must be supported by rollers on two concen 70 tric rails, the gas-permeable bottom being an integral part of the carrying frame.

In a case of an annular cooler discharged through the bottom and an annular cooler which is discharged by scraping cooled mat 75 erial from a bottom plate, it has been proposed that the cooling compartment be formed by cells arranged one beside the other and movably secured to a carrying frame so that thermal stresses are not 80 transmitted to the carrying frame and the latter is not subjected to wear by the material being cooled However, the carrying frame spans the interior of the cooler.

An annular cooler has been disclosed in 85 which the outer wall of the cooling compartment stands on the bottom plate and is freely movable thereon so that the outer wall does not transmit thermal stresses to the carrying structure, concentric guidance 90 N_ N 1 579 367 being effected by a central bearing, and the carrying frame spanning the interior of the cooler.

It is an object of the invention to avoid or reduce the disadvantages of the previously proposed coolers in which the cooled material is discharged by being scraped from the bottom plate, and in particular embodiments of the invention to provide a cooler having an interior which is free of a carrying frame, to protect the carrying frame from thermal stresses and from wear which is due to abrasion by the material to be cooled, and to provide a cooler which has a statically determinate structure that is as light in weight as possible.

According to the present invention there is provided a rotatable annular cooler for cooling hot bulk material, comprising an annular bottom plate, which consists of a rigid disc, a carrying frame secured to the bottom plate, an annular cooling compartment, which is mounted on the carrying frame and has gas-permeable inner and outer walls, at least the lower edge of the outer wall being spaced from the bottom plate, the carrying frame carrying the walls of the cooling compartment consisting of a cylinder, which is radially stiffened by corner pieces on the disc and is stiffened on the inside in its upper portion by a peripheral ring, a charging device above the cooling compartment, a scraper disposed above the bottom plate so as to be disposed in the cooled material when present, drive means for rotating the cooler, means disposed on the inside of the carrying frame and serving to supply a gaseous cooling fluid, and one or more blowers for producing the pressure required for the cooling fluid, flangeless track rollers, which are rotatable about vertical axes and which serve horizontally to guide and to centre the cooler being provided on the inside of the disc and being guided by the cylindrical surface of a first circular flangeless track rail, and vertical forces being transmitted from the cooler to the annular surface of a second circular flangeless track rail by flangeless rollers, which are rotatable about horizontal axes and which are disposed below the disc.

In this Specification the term "cylinder" is used to mean a circular cylinder as well as to mean a polygonal cylinder, which is open at its top and bottom, and the terms "inner" and "outer" are used in relation to the centre of the cooler.

The rigid disc preferably consists of radially and horizontally extending bars, which are rigidly interconnected at their ends by horizontally extending bars, and is stiffened by bracing arranged in the regions between the bars, these regions being covered by plates The plates may be loosely applied and held in position by abutment, or the plates may be fixed in position This arrangement results in a rigid disc which is light in weight.

The cylinder preferably consists of upright rods and is stiffened by lattice brac 70 ing in alternate regions defined by the rods.

Alternatively, the cylinder may be stiffened by lattice bracing in each region although this is not necessary in practice These arrangements result in a rigid cylinder which 75 is light in weight.

The corner pieces are conveniently arranged on the outside of the cylinder so that the corner pieces are disposed in a dead space and do not occupy a space which is 80 required for other purposes In principle, the corner pieces could also be disposed on the inside.

The peripheral ring is preferably formed from a plurality of I-section bars or girders, 85 which are joined together and each of which has a horizontal web and a height of at least 600 mm This results in a good stiffening by means which are light in weight.

The walls of the cooling compartment 90 may be formed by individual cells, which are arranged one beside the other and which are hung on a fixed support in the lower portion of the cylinder and on a movable support in the upper portion of the cylinder As a 95 result, thermal stresses are not transmitted to the carrying frame and the latter is not subjected to wear.

The lower portion of the cylinder may include a bracket, and the inner wall and the 100 outer wall of the cooling compartment may consist of annular walls which are radially displaceably carried by the bracket, the displacement being limited by stops For reasons of manufacturing technology, the 105 annular walls are usually polygonal although they may, alternatively, be circular because in that case too thermal stresses will not be transmitted to the carrying frame and the latter will not be subject to wear 110 Preferably, the outer wall is stiffened on its outside at least in its upper portion by a peripheral ring and at least the upper portion of the cylinder is provided with spacers for ensuring the configuration of the inner 115 wall The peripheral ring for stiffening the outer wall may be arranged in the outer wall itself As a result, the pressure applied to the wall by the material being cooled is taken up in a simple manner 120 An air duct in the shape of a circular ring may be provided on the inside of the cylinder and the blower(s) may be accommodated in the interior of the cooler and connected to the air duct by connecting con 125 duits As a result, the interior of the cooler can be used to accommodate the blower(s).

The cooling air may alternatively be sucked through suction ducts from the outside of the cooler so that sucking of heated cooling 130 1 579 367 air is avoided.

A stationary roof is conveniently associated with the cylinder so that the latter together with the roof defines a plenum chamber for cooling fluid to be supplied, and supply conduits lead from the blower(s) to the cylinder The supply conduits leading from the blower(s) may open into the plenum chamber from above through the stationary roof and from below This arrangement will mainly be used when the interior is too small to accommodate blower(s).

The air duct and/or the plenum chamber for the cooling fluid to be supplied may be shut off by a stationary partition and sliding seals adjacent to the charging area and the discharge area from the rotating inside surface of the cylinder, the stationary partition being extended in length before and behind the charging and discharge areas at least by the distance between two vertical rods of the cylinder This arrangement prevents, in a simple manner, an ingress of cooling air into the charging and discharge area Any ingress of cooling air into this area would result in the raising of much more dust.

An upwardly flaring peripheral sheet metal shell forming an air guide ring is conveniently provided on the outer wall of the cooling compartment at the lowermost outlet for the cooling fluid This ring flares upwardly in such a manner that it does not influence the velocity of the gas As a result, any heated cooling air which escapes in the lower portion of the compartment is deflected in an upwardly inclined direction and any fine particles which may have been entrained are returned.

The cooler has a charging station and a discharge station which are preferably arranged one over the other so that the useful cooling area is increased and a single partition for confining the inflowing cooling air and a single dust collector are sufficient.

The inner and outer walls of the cooling compartment preferably terminate in gasimpermeable upper and lower portions extending for a length which exceeds the thickness of the layer of material in the cooling compartment so that upward and downward escape of heated cooling air from the cooling compartment is virtually avoided.

In order to enable the invention to be more readily understood, reference will now be made to the accompanying Drawings, which illustrate diagrammatically and by way of example some embodiments thereof, and in which Fig 1 is a transverse sectional view of a cooler for hot bulk material, the cooler having cooling cells or continuous annular walls, Fig 2 is a view showing a portion of the cooler of Fig 1 developed into a plane and viewed in the direction of arrows A-A in Fig 1, the cooler being adapted to accommodate cooling cells, Fig 3 is a sectional view taken on the line B-Bin Fig 1, 70 Fig 4 is a sectional view showing one half of a cooler for hot bulk material and provided with cooling cells and with diagrammatically shown means for supplying air from above into a plenum chamber, 75 Fig 5 is a sectional view showing one half of a cooler for hot bulk material and having a cooling compartment consisting of continuous annular walls, means for supplying air not being shown, 80 Fig 6 is a sectional view is taken on the line C-C in Fig 1 and represents a charging and discharge area, Fig 7 is a sectional view showing one half of a cooler for hot bulk material having cool 85 ing cells and diagrammatically shown means for supplying air to an air duct having the shape of an annular ring, blowers being provided in the interior of the cooler, Fig 8 is a fragmentary top plan view 90 showing a cooler for hot bulk material similar to that shown in Fig 1 having cooling cells The cooler has means (not shown) for supplying air to an air duct having the shape of a circular ring, and blowers are accom 95 modated in the interior of the cooler.

Referring now to the Drawings, Fig 1 shows an annular cooler for hot bulk material, the cooler including a rigid disc 1 which ensures the peripheral stiffness of the annu 100 lar cooler A cooler compartment 3 has walls 2 and 2 a which are loosely hung in a carrying frame consisting of a stiffened cylinder 4 The stiffened cylinder 4 is fixedly connected to the rigid disc 1 by triangular 105 corner pieces 5 and is stiffened on the inside in its upper portion by a peripheral ring 6 formed from a plurality of individual girder sections joined together The cooler is horizontally guided by flangeless guide rollers 7, 110 which roll on a circular track rail 8 Flangeless rollers 9 are provided for transmitting all vertical loads to a track rail 10, which is firmly anchored in a concrete foundation.

The cooler is charged via a charging chute 115 32 and is discharged by means of a knife scraper 33 The cylinder 4 is covered by a stationary roof 28 with which it defines a plenum chamber 29 for cooling fluid, which is supplied through a conduit 30 from a 120 blower, partitions 34 keeping the cooling fluid from a charging area 32 and a discharge area 33 of the cooler.

The cylinder 4 is shown in Fig 2 in elevation in the direction of arrows A-A in Fig 1, 125 without the cooling compartment, the cylinder 4 consisting of upright rods 15, which are stiffened by bracing 16 in regions between alternate pairs of rods The number of braced regions can be varied The 130 1 579 367 peripheral ring 6 connects the free ends of rods 15 to form a frame defining the cylinder 4, which is firmly connected to the rigid disc 1 by the corner pieces 5 Vertical loads are transmitted from the disc 1 to the rollers 9 rolling on the circular track rail 10 A cell 17 of the cooling compartment can be loosely hung in each stiffened region on supports 18 and 19.

Fig 3 is a top plan view of the rigid disc 1.

The guide rollers 7 rolling on the track rail 8 are firmly connected to the rigid disc 1 and guide the latter horizontally about the centre of the cooler The rigid disc 1 consists of radially and horizontally extending bars 11, which are stiffly connected at their ends by horizontally extending bars 12 in such a manner that a polygonal annular plate is formed The resulting regions between the bars 11 are stiffened by bracing 13 or solid web girders of sheet metal The resulting framework is covered with plates 14 which form a surface for supporting the material to be cooled.

Fig 4 shows how a cell 17 is hung in the cylinder frame 4 in a fixed lower support 18 and a movable upper support 19 Material to be cooled rests on the plates 14, which are so arranged that they can expand freely.

The guide rollers 7 are horizontally aligned and transmit guiding forces to the circular track rail 8.

Cooling air flows from the blower through the air supply duct 30 into the plenum chamber 29 The partitions 34 which prevent the cooling fluid from entering the charging and discharge areas are secured in this case to the stationary supports for the roof 28 Where the plenum chamber 29 is provided, the cooling fluid can be supplied from above and from below.

The inner wall 21 and the outer wall 22 of the cooling compartment shown in Fig 5 stand on peripherally spaced brackets 20, which are secured to the carrying frame and to the rigid disc Each bracket 20 carries spacers 23 for the inner and outer walls, these spacers ensuring the circular configuration but permitting the walls to expand in case of a temperature rise The same purpose is served by upper spacers 25, which are secured to the carrying frame A peripheral ring 24 formed from a plurality of sections on the outer wall serves to take up the pressure exerted from the inside of the cooring compartment A sheet metal air guide 36 serves to deflect heated cooling fluid throughout the periphery and cause it to flow upwardly at an unchanged velocity, whereas any entrained fine particles which fall back are returned to the cooling compartment.

The cooling fluid is prevented from entering the charging area 32 and the discharge area 33 by the stationary partitions 34 and sliding seals 35, which are secured to the vertical rods 15 The rigid disc 1 is provided with the vertical rods 15, which are stiffened by the triangular corner pieces 5, and with the applied plates 14 and rotates around the 70 centre of the cooler past the stationary partitions 34 and the discharge device 33.

Fig 7 shows a modification in which the blowers 27 are accommodated in the interior of the cylinder Because of this 75 arrangement the plenum chamber 26 may have the shape of a circular ring, the blowers 27 being connected to the plenum chamber 26 by an adapter The cooling air can be sucked directly in the interior or through 80 suction ducts from the outside.

The rigid disc 1 and the upright rods 15 are shown in Fig 8 which is a fragmentary top plan view of the cooler The rods are stiffened by bracing 16 in alternate regions, 85 and the free upper ends of the rods 15 are connected to the ring 6 The cells 17 are loosely hung in mountings on the rods 15, and sheet metal air guides 36 are provided throughout the periphery 90 An advantage of the present cooler is that it can be provided with a structure which is light in weight, the interior is kept free, and the carrying frame is kept free from thermal and mechanical stresses 95

Claims (1)

1. WHAT WE CLAIM IS:

   1 A rotatable annular cooler for cooling hot bulk material, comprising an annular bottom plate, which consists of a rigid disc, a carrying frame secured to the bottom plate, 100 an annular cooling compartment, which is mounted on the carrying frame and has gas-permeable inner and outer walls, at least the lower edge of the outer wall being spaced from the bottom plate, the carrying 105 frame carrying the walls of the cooling compartment consisting of a cylinder, which is radially stiffened by corner pieces on the disc and is stiffened on the inside in its upper portion by a peripheral ring, a charging 110 device above the cooling compartment, a scraper disposed above the bottom plate so as to be disposed in the cooled material when present, drive means for rotating the cooler, means disposed on the inside of the 115 carrying frame and serving to supply a gaseous cooling fluid, and one or more blowers for producing the pressure required for the cooling fluid, flangeless track rollers, which are rotatable about vertical axes and which 120 serve horizontally to guide and to centre the cooler being provided on the inside of the disc and being guided by the cylindrical surface of a first circular flangeless track rail, and vertical forces being transmitted from 125 the cooler to the annular surface of a second circular flangeless track rail by flangeless rollers, which are rotatable about horizontal axes and which are disposed below the disc.

   2 An annular cooler as claimed in 130 1 579 367 Claim 1, wherein the rigid disc consists of radially and horizontally extending bars, which are rigidly interconnected at their ends by horizontally extending bars, and is stiffened by bracing arranged in the regions between the bars, these regions being covered by plates.

   3 An annular cooler as claimed in Claim 1 or 2, wherein the cylinder consists of upright rods and is stiffened by lattice bracing in alternate regions defined by the rods.

   4 An annular cooler as claimed in any one of Claims 1 to 3, wherein the corner pieces are arranged on the outside of the cylinder.

   An annular cooler as claimed in any one of Claims 1 to 4, wherein the peripheral ring is an I-section ring which has a horizontal web and a height of at least 600 mm.

   6 An annular cooler as claimed in any one of Claims 1 to 5, wherein the walls of the cooling compartment are formed by individual cells, which are arranged one beside the other and which are hung in a fixed support in the lower portion of the cylinder and in a movable support in the upper portion of the cylinder.

   7 An annular cooler as claimed in any one of Claims 1 to 5, wherein the lower portion of the cylinder includes brackets, and wherein the inner wall and the outer wall of the cooling compartment consist of annular walls which are radially displaceably carried by the brackets, the displacement being limited by stops.

   8 An annular cooler as claimed in Claim 7, wherein the outer wall is stiffened on its outside at least in its upper portion by a peripheral ring and at least the upper portion of the cylinder is provided with spacers for ensuring the configuration of the inner wall.

   9 An annular cooler as claimed in any one of Claims 1 to 8, wherein an air duct in the shape of a circular ring is provided on the inside of the cylinder and the blower(s) is (are) accommodated in the interior of the cooler and connected to the air duct by connecting conduits 50 An annular cooler as claimed in any one of Claims 1 to 8, wherein a stationary roof is associated with the cylinder so that the latter together with said roof defines a plenum chamber for the cooling fluid, and 55 supply conduits lead from the blower(s) to the cylinder.

   11 An annular cooler as claimed in Claims 9 and 10, wherein the air duct and/or the plenum chamber for the cooling fluid to 60 be supplied is shut off by a stationary partition and sliding seals adjacent to the charging area and the discharge area from the rotating inside surface of the cylinder, the stationary partition being extended in length 65 before and behind the charging and discharge areas at least by the distance between two vertical rods of the cylinder.

   12 An annular cooler as claimed in any one of Claims 1 to 11, wherein an upwardly 70 flaring peripheral sheet metal shell forming an air guide ring is provided on the outer wall of the cooling compartment at a lowermost outlet for the cooling fluid.

   13 An annular cooler as claimed in any 75 one of Claims 1 to 12, wherein the cooler has a charging station and a discharge station which are arranged one over the other.

   14 An annular cooler as claimed in any one of Claims 1 to 13, wherein the inner 80 wall and the outer wall of the cooling compartment terminate in gas-impermeable upper and lower portions extending for a length which exceeds the thickness of the layer of material in the cooling compart 85 ment.

   An annular cooler for hot bulk material substantially as hereinbefore described with reference to the accompanying Drawings 90 TREGEAR, THIEMANN & BLEACH, Chartered Patent Agents, Enterprise House, Isambard Brunel Road, Portsmouth PO 1 2 AN, and 49/51, Bedford Row, London, WC 1 V 6 RL.

   Printed for Her Majesty's Stationery Office by The Tweeddale Press Ltd, Berwick-upon-Tweed, 1980 Published at the Patent Office, 25 Southampton Buildings, London, WC 2 A l AY, from which copies may be obtained.